Search Results

Since the 1960's, lightning protection of aircraft has been an important design aspect, a concern for the flying public, aircraft manufacturers and the Federal Aviation Administration (FAA). With the implementation of major aircraft structures fabricated from carbon fiber reinforced plastic (CFRP) materials, lightning protection has become a more complicated issue to solve. One widely used material for lightning strike protection of CFRP structures within the aerospace industry is expanded metal foil (EMF). EMF is currently used in both military and commercial passenger aircraft. An issue that has historically been an area of concern with EMF is micro cracking of paint on the composite structure which can result in corrosion of the metal foil and subsequent loss of conductivity. This paper addresses the issues of stress and displacement in the composite structure layup which contribute to paint cracking caused by aircraft thermal cycling.

Clothing can constitute a major logistical problem for advanced missions. Current and historical clothing systems for space missions have been assessed, as has the viability of using a washing machine to clean (recycle) clothing. Modern fabrics can reduce the mass and increase the functionality of clothing, including reducing the risk of fire, for all missions. The increased cost of acquisition of even high tech commercial off the shelf (COTS) items is trivial compared to the cost of shipping the clothing and disposing of it as trash. Washing can be cost effective when water is recycled efficiently, provided the mission is long enough. The breakeven time for clothes-washing depends on the specifics of the mission, particularly the mass equivalencies of infrastructure, but is of the order of weeks rather than years.